Water turbines are a growing trend as the flow of water is increasingly looked to as a natural resource from which electrical power may be harnessed. There are several means of positioning turbines in water flow, including tidal flow, wave flows and current flows. A particularly popular means of positioning a turbine in a current flow is to position the turbine upon a floating platform.
The present invention overcomes the flaws inherent in the prior art of floating platforms supporting turbines in water flows. Previous innovations in the field of floating platforms for turbines are affected by drag. Drag generally arises from two aspects of prior art platforms. First, most prior art platforms are rigidly moored so as to cause the platform to remain as stationary as possible in flowing water. This positioning creates drag upon the elements of the platform that are in the water. For example, the flow of the water exerts excess torque on rotor that creates drag. This occurs because the rotor is virtually stationary in a flow of water. Second, drag is experienced by the platform as it sits in the water. The platform struggles to hold its position in the water as the turbine is functioning and as a result of this activity areas of the platform may be pulled under the water, which creates drag. It furthermore causes the platform surface to be un-level and the platform as a whole to be unstable.
An example of the prior art is disclosed in U.S. Pat. No. 4,940,387. The invention disclosed therein includes a structure, such as a barrage, utilized to position a water turbine in the path of a water source. The structure extends across and above the level of the water source and the turbine is mounted within a casing situated under the water level that extends downwards as a segment of the structure. The structure is supported from below, for instance by a piling.
US Patent Application No. 2003/0014969 discloses another configuration of a platform. An apparatus comprising two spaced, parallel, hollow side members is applied in this prior art example. The side members are formed to have inwardly facing sloping end faces, to allow the upstream end of the body to divert water into the channel between the side members. Turbine rotors are attached to the water facing side of cross bars positioned to extend between the side members. The platform is anchored by lines attached to each corner of the structure.
These prior art examples are configured in a manner that leaves them susceptible to experience drag. The means of anchoring the platforms can cause an instability whereby the platforms are un-level and drag pulls a portion of the platform underwater. Additionally strict positioning of the turbine from the platform creates drag upon the turbine rotor. Furthermore, the structures do not allow for easy transfer between locations. An invention is needed that overcomes these problems inherent in the prior art.